This silky serum contains high amounts of vitamins C (ascorbic acid) and E (in the form of tocopheryl acetate, which isn’t pure vitamin E but still has benefits). We don’t doubt the concentrations stated in the product’s name, but what is definitely questionable is the inclusion of two fragrant oils known to cause irritation. A high amount of ascorbic acid can be irritating on its own (it is an acid, after all), so for best results with high-strength vitamin C serums you want to avoid the needless irritants this one contains. See More Info to learn why irritation is bad for all skin types.

If a serum with a high amount of vitamin C is what you’re after (though we must mention that vitamin C is far from the only ingredient your skin needs, much like your diet would suffer is all you ate were oranges), check out the options from SkinCeuticals or Cellex-C and leave this one on the shelf.

Amount and form of vitamin C may prove too irritating, tipping the scales away from benefits and toward skin problems.

Contains irritating fragrant oils.

Lacks a range of anti-aging ingredients to help your skin in numerous ways, and lacks skin-repairing and cell-communicating ingredients.

More Info:

Irritation, whether you see it on the surface of your skin or not, causes inflammation and as a result impairs healing, damages collagen, and depletes the vital substances your skin needs to stay young. For this reason, it is best to eliminate, or minimize as much as possible, your exposure to known skin irritants, especially when there are brilliant formulas available that do not include these types of problematic ingredients. Although this serum contains vitamin C to help stimulate collagen production and repair skin, there are others that do the same thing, but without the downside of irritants to keep the good ingredients from providing their maximum potential benefit.

Claims

C-Strength contains a stable and effective vitamin C and E topical for skin strengthening and brightening, as well as fine line and wrinkle smoothing. This powerful formula pairs 20% vitamin C with 5% vitamin E, the ideal amount for topical absorption into normal skin types.

Weaknesses: Way too expensive for what you get; several products contain irritating fragrant oils; the toners contain irritants; there are too many serums and many contain irritating ingredients; the acne products contain problematic ingredients.

PCA Skin is a product line you may have seen at your spa, salon, or dermatologist's office. Founded by an aesthetician in 1990, the brand became relatively popular after developing a series of professional alpha hydroxy acid (AHA) peels marketed as "medical clinical aesthetics"; in other words, these products are sold to dermatology practices offering cosmetic services such as facials. More recently, PCA Skin has teamed up with a dermatologist and other medical professionals to develop skin-care products. The peels are for professional use only and, in fact, except for a facial scrub, PCA Skin does not sell exfoliants that consumers can use at home.

Not surprisingly, PCA Skin's medical and aesthetics background is supposed to be rooted in science. The company states that "we use rigorous research and science to develop safe, highly effective products that deliver healthy, beautiful skin." Although PCA Skin products contain many beneficial, research-supported ingredients, they also contain numerous problematic ingredients that cause irritation; somehow, that "rigorous" research overlooked those. Irritation is always a problem for skin, causing inflammation and collagen breakdown, and impairing the skin's ability to heal.

Chief among the irritants you'll find throughout the PCA Skin line are witch hazel, citrus and numerous other fragrant oils (whether synthetic or natural, fragrance is almost always a problem for skin), drying cleansing agents, and alcohol (we mean, really, alcohol?!). In our Cosmetic Ingredient Dictionary, we provide detailed information on why each of these ingredients is a problem; for all of their talk about science, chemistry, and research, PCA Skin should know better.

If you remain intrigued by this brand (or find the sales pressure from your aesthetician too intense to ignore), there are some worthwhile products. It’s great that every SPF-rated product from PCA Skin includes reliable broad-spectrum sun-protection ingredients, and fans of facial scrubs should know this brand does offer a gentle option. Also, their eye cream and retinol serum are worth a look, and several products are fragrance-free, although you need to choose carefully because many of their products contain fragrant plant extracts or oils despite being listed as fragrance-free.

PCA Skin's science-based mission is admirable, but just because an aesthetician and doctor teamed up, the results for these products aren't going to be spectacular, or even all that helpful.

For more information about PCA Skin, call (877) 722-7546 or visit www.pcaskin.com.

About the Experts

The Beautypedia Research Team is dedicated to helping you find the absolute best products for your skin, using research-based criteria to review beauty products from an honest, balanced perspective. Each member of the team was personally trained by Paula Begoun herself.